Magnetic recorder



Aug. 11, 1953 M. cAMRAs MAGNETIC RECORDER 5 Sheets-Sheet l Filed Dec. e, 194'? Aug. 1l, 1953 M. cAMRAs,

MAGNETIC RECORDER 5 Sheets-Sheet 2 Filed Dec. 6, 1947 .,I Imm H 42, 4L o H. 1|. rh I l um I n u I m n O IIJ, 4%..,

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Aug. 11, 1953 M. cAMRAs MAGNETIC RECORDER SSheet's-Sheet 3 Filed Dec. 6, 1947 :z-zerz DI' yew/v (J7/veas' J/i n M Aug. 1l, 1953 M CAMRAS MAGNETIC RECORDER 5 Sheets-Sheet 4 Filed Dec. 6, 1947 rm Dm Ausfn 11, i953 M. CAMRAS' 2,648,590

MAGNETIC RECORDER Fil-af. DBC. 5, 194'? 5 Sheets-Sheet 5 :nz-Er: Zar-f Nauw/v 6fm/Qns Patented Aug. l1, 1953 UNITED STATES FATENT OFFICE MAGNETIC RECGRDER Illinois Application December 6, 1947, Serial No. 790,193

14 Claims.

My invention relates to drive mechanism for magnetic recorders and more particularly to an improved drive mechanism suitable for use in a magnetic recorder or the type wherein a removable cartridge or magazine containing a lengthy recording medium is inserted or removed from the mechanism.

In magnetic recording devices it is frequently desirable to provide a mechanism whereby a simple operation permits the medium to be removed or added thereto, thus enabling the user quickly to reproduce different intelligences or to supply fresh medium for the purpose of recording a continuing intelligence. Moreover, it is desirable that this addition or removal of the medium-containing cartridge or magazine be accomplished in a simple and direct fashion without the need to unwind and thread the medium through a complicated series of capstans, guide wheels, etc. Furthermore, a rewind mechanism capable of rewinding the medium at high speed without unduly tending to break the medium is highly desirable to the end that the time lost in this operation be minimized.

In magnetic recorders of the type intended for use with removable cartridges or magazines, it is further desirable to provide a mechanism suitable ior use with a cartridge containing only the spool or reels upon which the medium is wound and having no other elements, to the end that cartridges or magazines of minimum cost may be used.

It is accordingly a general object of the present invention to provide an improved magnetic recorder suitable for use with a cartridge or magazine.

Further, it is an object of the present invention to provide an improved magnetic recorder of the type wherein a cartridge or magazine containing the medium may be readily and easily inserted without threading the medium over guide pulleys or other mechanism.

Further, it is an object of the present invention to provide an improved magnetic recorder wherein the medium is automatically distributed over the axial length of the reels or spools in the cartridge or magazine.

A further object of the present invention is to provide an improved magnetic recording mechanism which is operable to wind the record medium in either direction to permit recording or reproducing and rewinding as well, and which has interlocking elements to free the medium of the transducer head during rewind.

It is yet another object of the present invention to provide an improved magnetic recorder wherein the medium may be rewound at high speed with minimum tendency toward breakage.

Still another object of the present invention is to provide an improved magnetic recorder capable of receiving medium containing cartridges or magazines containing only the spools or reels upon which the medium is wound.

My invention further resides in the features of construction, combination and arrangement whereby an improved magnetic recording mechanism is provided which is simple and inexpensive in construction and reliable in operation, to the end that a unit of maximum utility is provided.

The novel features of my invention are set forth with particularity inthe appended claims. My invention itself, however, both as to its organization and method of operation, may best be understood by reference to the following description taken in connection with the accompanying drawings, in which:

Figure 1 is a front elevational view of a mechanism embodying the principles of the present invention, with the housing broken away to expose the operative elements;

Figure 2 is a side cross-sectional view taken through the axis II-1I, Figure l, with the hous ing removed to show the operative elements;

Figure 3 is a front elevational view of the mechanism of Figure 1 but with a magazine containing a pair of spools and a lengthy recording medium wound thereon inserted, and with the head in theoperating position.

Figure 4 is a top plan View of the mechanism of Figures 1 and 2 with the housing broken away to show the magazine and operating elements;

Figure 5 is a rear elevational view of the mechanism of Figure 1 and with the housing removed;

Figure 6 is a fragmentary front elevational view of an alternative embodiment of the present invention;

Figure 7 is a fragmentary top plan view of the embodiment of Figure 6;

Figure Sis a front elevational view of the bridge which imparts inward and outward movements to the retractable carriage;

Figure 9 is a top plan view of the carriage portion of the mechanism;

Figure 10 is a cross-sectional view through the axis X-X of Figure 4, showing a spool received on one hub portion of the mechanism;

Figure 11 is a fragmentary cross-sectional view through the axis XI-XI, Figure 2, and showing the structure of the operative elements;

Figure 12 is a fragmentary cross-sectional View like Figure 2 but showing the carriage in the further retracted position to rewind the medium;

Figure 13 is a fragmentary cross-sectional view through axis XIII-XIII, Figure 2, but showing the elements in position corresponding to the retraction of the head and with parts in elevation; i

Figure 14 is a fragmentary cross-sectional View through the axis XIV-XIV, Figure 2, showing the drive mechanism for the take-up spool hub;

Figure 15 is an enlarged fragmentarycrosssectional view through axisXV-XV, Figure lll; and

Figure 16 is a fragmentary side. elevational view showing the guide attached to the carriage to guide the medium in its travel thereover.

Referring now to the mechanism of Figure l', there is shown at 2c a front panel which is supported upon the legs 22 and which is held in en gagement with the rear panel` 2li- (Figure 2) by the sleeves 2S which receive the screws extending through the panel 2e. As shown in Figure 5, the rear panel 24 is held to the sleeve 25 by the screws Bil. A pair of shafts 32 and Sil extend forwardly from the panel and receive the hubs or collars 35 and 33 which are press-fitted thereon andv engage the spool upon which the lengthy record medium is` wound. Figure l0 is a crosssectional view showing the shaft ,32 and the hub 36.

The construction of the hubs 35 and 33 may best be seen by the cross-sectional view of Figure 2 which shows the hub 35 in elevation. As indicated, this hub includes a forwardly extending a,

member 36e isy sustained by an adhesive to the.

front portion of the ange section 3,519. The hubBS includes a flange portion 3819, a forwardly extending cylindrical portion 38a and an annular friction member 33e (Figure l) in like fashion. As will be described in further detail hereafter, the magazine contains a pair of spools, each of which has a central opening to receive the cylindrical portions 35a and 38a of the hubs 55. and'v 38 and which has side portions tov engage the annular friction members 36e and 38C to drive or oppose the rotation of the spools in accord with the operation of the mechanism.

A pair of hook-shaped rods ill and d?! of circular cross-section are mountedV with their lengthy legs elle and liZ-a extending, through basel bearings lll and l5 in the panel 2G. A bridge 48 extends between these rods as is best seen in the views of Figures 2 and 4. This bridge is held against the portion 42a of rodZ by forcing screw 45a, and against the portion 4M of rod lic by forcing screw 45h. The member 48. has an upstanding dome 43e which has a cylindrical opening i3d to receive the shaft 50 which extends in a direction normal to the plane of the panel 25.

The shape of bridge 48 is. best seen in the view of I tem portion of the core.

at like velocity, repeating this cycle of operation once for every four revolutions of the shaft 50.

A carriage 52 extends between the legs mb and i219 of the shafts @il and d2. This carriage has openings 53 (Figure 9) which slidably receive these shafts and support the head 55 and the pinch wheel '52. The carriage vr52 is further sustained upon the U-shaped bar 56 which is best seen in the View of Figure 9 and which bears elongated slots 5% (Figure 2) at its opposite end portions 55a and 55h. The carriage 52 has a pair of pins 52a and 52h which are received in the slots 58 to cause the carriage 52 to partake of the up-and-down movement of the support bracket 5S. These slots are elongated to permit the carriage 52 to partake of the horizontal movement` of the arms d@ and t2 Without causing movement to be imparted to the Ushaped support bracket 56 which is mounted adjacent the panel 25.

The vertical movements of the carriage 52 are controlled by the rack 6l? and the pinion 52 (Figure l). The former is received in the spaced guides lill and @it which slidably received that` member. rThe pinion 52 is attached to the shaftA 58 (Figure 2) which in turn is rotated by knob l0. The U-shaped support bracket 5571s held in engagement with the rack 55 by a notched slot portion which faces. the panel 2c to receive bracket 55 as shown in Figure 2. If desired, the U-shaped support 55 may be attached to the. rack 55 by welding or other suitable means.

The head 55 is mounted upon the carriage 52 by suitable support screws (not shown) and may be any one of several types well known in the art. For example,this head may include a U-shaped core listo; having leg portions defining confronting pole pieces at the upper portion of the head 54 and which has a winding encircling the bot'- The confronting pole pieces of the core 54a are mounted against the bottom of the groove 54e (Figure .2) which receives the lengthy wire constituting the magnetiaable record medium. y

When it is desired to impart variations in the degree of magnetization of the medium as it passes across the head 54, electric current varying with time in accordance with the timeV variations in they intelligence to be recorded is impressed across the coil 56.19 to. vary the intensity of the magnetic field between the confronting pole pieces of the core portion 54a in accordance with the time variations of the intelligence. As the medium rides over the head 54,. corresponding variations in the degree of magnetization are. imparted to the medium to magnetize the medium. along its length in accordance with the time variations of the intelligence. During reproducel tion, themedium is drawn over the head 5:1 to.

.A capstan 'lil is mounted upon the panel. and is vsustained upony the shaft 'ES which ex`` tends through panels 2c and 2li. As shown -i-n Figure 4, this capstan is relatively lengthy' and is of sufficient length to bear against the medium passing over the headl 54 even when the latter sin the two extremes of'horizontal'inovement caused by the bridge 48.

' In accordance with one feature of the present invention, the capstan 14 is covered with rubber or similar material to accomplish effective gripping action against the medium. Since the carriage 52 is continuously moving in direction transverse to the panel 20, the point at which the medium rides on the surface of capstan 14 is continuously changing, and uniform Wear over the entire surface is achieved.

Figures 3 and 4 show a magazine 18 in operative engagement with the structure of Figure l. 'Ihis magazine includes a pair of spaced spools 80 and 82 which are spaced from each other by distance corresponding to the spacing of shafts 32 and 34 and are shaped to be received upon the collars 36 and 38. The shape of the spools 80 and 82 is best seen in the view of Figure 10 which shows la cross-sectional view through the axis of Xf-X (Figure 4). Each of these spools is urged against the friction surface of the corresponding collar 36 or 38 by the bowed resilient members 84 and 06, respectively. These are each mounted on the forward panel 18a of the magazine 18 and urge the spools rearwardly relative to the panel 18a and against the collars 35 and 38. The magazine 18 is provided with a plurality of knobs 83 to permit insertion and removal thereof to and from the recess defined by the housing H.

If it is desired to minimize the storage space required by magazine 18, indentations may be provided in the panel 18a to permit removal of the magazine from the recorder. The knobs 8B can thereby be eliminated.

- It will be evident from the foregoing that the magazine 18 consists only of a housing portion containing a pair of medium supporting spools or reels 80 and B2 upon which the medium 9G is wound, and a pair of bowed springs 84 and 855 to'urge these spools against the rear wall thereof. .When the magazine is inserted, the spools 80 and 82 are supported from the hubs 36 and 33, Figure 1, as shown in Fig-ure 10. Thus a simple and inexpensive magazine containing no shafts, capstans, electromagnetic transducer heads, or like equipment, may be used with the apparatus of the present invention, and the expense associated with the use of magazines is minimized. If desired, resilient snap elements 92 may be mounted on the forward portion of the housing H to bear against the magazine 13 to urge the magazine into engaged relationship with this housing. The bias of these elements is overcome to .insert or remove the magazine.

A lengthy magnetic record medium 9i) of wire or the like extends between the spools 80 and 82, as will vbe evident from Figures 3 and 4. This medium leaves these spools at the tcp portions thereof and thus rides free of the head 54 when the latter is in the retracted position shown in Figure 1 as indicated by the dashed line 55 which indicates the position of the medium when free of head 54 and pinch wheel 12. It will further beevident from Figure 1 that the medium 90 rides beneath the capstan 14 when the pinch wheel 12 is in the retracted position of that gure.A Consequently, the magazine 13 may be inserted in the mechanism without requiring the medium 90 to be threaded over the capstan 14, the pinch pulley 12, or the head 54, and may be inserted into the housing H by the simple operation of grasping the knob 88 and pushing the magazine into position.

I When the rack 60 is shifted upwardly by rotathe medium and cause the latter to ride onl the periphery of the capstan 14. Moreover, the pinch Wheel 12 engages the periphery of the capstan 14 to increase the frictional engagement between the medium 90 and the capstan, thus causing the medium to partake of the movement of the capstan and move with a linear velocity corresponding to the angular velocity thereof.

The capstan 14 is rotated simultaneously with shaft 50 by means to be described in further detail hereinafter. The former imparts linearI velocity to the medium 90, whereas the latter imparts movement on a horizontal axis to the bridge 52 and hence the pinch wheel 12 and the head 54. This causes the medium 90 to be Wound uniformly on the take-up spool and to provide a uniform distribution of that medium thereon. In addition, this, equalizes the engagement of medium 90 with capstan 14 over the length of that ca-pstan to cause uniform Wear thereof.

The capstan 14 is made of sufficient length to receive the medium 90 in all positionsvof the carriage 52.

In addition to controlling the vertical position of the carriage 52 to retract the pinch wheel 12 and the head 54, the rack 60 also controls the movements imparted to the medium 90. To this end, the rack 60 is attached to the arm 94 (Figure 2)*.which extends through the window 95 of panel 20 and upwardly to sustain connector 30. A pin 98 is attached to connector 96 and extends rearwardly to engage the bentover portion of the shiftable control plate |00.V The construction and operation of the shift--r able control plate |08 can best be understood' by reference to the views of Figures 2, 4, 5 and 11. As will be evident from Figures 4 and 5,

the shiftable support plate |06 has a horizon-4 tally disposed portion |000, which denes an arm extending parallel to the plane of the panel 20 and which at its remote end contains the hooked portion |0019.y It is this portion that is engaged bythe pin 98, Figure 4. The shiftable plate |00 further has a vertically disposed portion |00e whichv is held against the outward surface of rear panel 24 by the overlapping head por-,3

tion of the screw |02. The shank portion |0241,

Figure 11, of this screw forms a stop member As is best.' shown in Figure 11, the portion |00b of the. shiftable plate |00 supports the selectively en-i gageable friction drive Wheel |04 which is pivot' against which the plate |00 rests.

ally supported by the shaft |04@ which receives the screw I 04h (Figure 5) which screw holds the inner race Yportion |04c of the bearing for'- wheel |04.

From the foregoing it will be evident that as the hook portion |001) of the plate |00 is en' gaged by the pin S8 and shifted downwardly,

the Wheel |04 is shifted to the position of the.

dashed lines of Figure 5 and thereby shifts into pinching relationship with the drive wheel |06 andthe driven Wheel |08. attached to the shaft 32 upon which hub 36 is mounted and thus acts to rotate that hub when.

A supplementary shiftable support plate Hi8V (Figures'g5 and 1l) shifts the Wheel I|0 into |Ihe latter Wheel is acierto@ 7 and out of .pinching relationship "with ythe A'drive wheel v'|116 and the yflywheel |F2. The latter is connected to the shaft 16 upon which the capstan |54 is mounted.

The plate |08 is 'of teardrop shape and has an extending pin 1080i-positioned to Vengage fthe corresponding extension 1|00c of 'the vplate |100. The plate |08 has fa circular Aopening '108e' which clears theshaft 'I6 as the vplate is rotated-about the -p'ivot formed by Ascrew f||4. Screw -||4 is received 'in panel '24. The wheel ||'0 is Isup'- ported from the shaft |00a which :is mounted upon fthe 'plate |08 fand =is held :in engagement with 'this "shaft by the screw ||10b (Figure 5') which is .received therein and sustains vthe Ainner race f| 1| 0c lof the Ibearing forming the inner portion of vthe wheel I|f|-||.

.As shown in Figures 5 and 11theplate |08 is provided with an opening IIJBd which receives the piano wire spring I I-G. At lits opposite 'end the spring ll |.6 :bottoms kagainst the head v'of screw |-'|8 which is received in 'the panel 24. `will be evident .from the "view of Figure 11,'thisspring acts to bias kplate .|08 in the counter-clockwise direction 'as lseen in that figure and thereby causes wheel to tend to pinch between the wheels 106 and H2. When this bias is vovercome by downwardrnotio'n of the :extension .|000 resulting from the "depression of the 'hook :porftion .|00b lof the plate L00, the wheel `lill is shifted out of engagement with the drive wheel |06 and 'the flywheel l|I|2, and the capstan 'i4 rides --f-reeof zrotations of drive wheel |05.

The plate |00 is provided 'with a recess lilld (Figures .and 51.1) t'oreceive 'the .piano wire spring -|-.0f|. This spring .is wrapped about the support post 22 .at its bottom end .acts .to bias the v*plate |500 .to the position of the :solid lines of Figure 'ythereby causing the hook limb to tend to rise upwardly and to -disengage the wheel |04.

.From the foregoing Iit will be evident that when 'the @pin 08 yis depressed, the Acapstan lTal rides :free of .any .motion Vimparted to .the drive wheel 106, and the friction 'wheel |106I swings into pinching relationship with wheels .|06 and |08 'to Idrive thecollar v:36.

:'As 'will be evident from Figure 2, the A.pin 98 rides free of the hook .portion |001) .of the Splat'e |00 'when ythe head 54 is shifted .to the .upward or operating condition as shown in `the 4:solid lines of `that View. Thus the capstan is 4then energized and Voperates to drive lthe .medium lill). However, when the head 54 is retracted `to .the position shown lin the .dashed lines ofrFigure 2, the pin :08 engages the hooked portion "Iilband rotates plate |60 to a degree suflicient to .cause the extension fitto to engage ythe pin lilac :and shift the friction wheel ||0 out of engagement with the vflywheel 1| 2, thereby releasing capstan 14.

In forder to hold the rack 50 in the retracted position against the actionof the bi'asing'springs |=|B aand f|0|, the -rack'60 .is provided with a "cupshapedfopenings 00a, Figure 2. This-opening Are'- ceives'the ballGBa, Figure 13, whichrides against the spring 06h which in 'turn :is ybottomed against thefadjustin'g screw 6.00. Thus,as ythe =knob .flllis rotated yto shift the vvhead54 to `.the retracted .position of -the 4dashedlines of` "Figure 2, theball 6 rides `in lthe cup 1000, `and iholds the rack .60 as show-n lin .Figure -13,"thus sustaining lwheel H0 in the disengaged position and holding ywheel |1|2ifree1o^f any-driving torque from `wheel j11H).

A similar cup-shaped opening 60h is provided 8 inthe rack j6|! "to receive the vball `66a when vthat rack is in position shown in Figure 3 where rthe head 54 :engages medium 90. This opposes .any tendency Aof the 'medium v90 to shift the `'head 5'4 and the associated mechanism .toward `vthe fretracted position.

In "the view of vFigure `12, the felements 'are shown `in a further retracted position wherein the rack 60 -is fheld against vthe bias of springs ||`6 and |0-| to a position beyond that icorresponding to the position wherein ball arides in cup 60a. In `this position lthe llower edge fof the connector 06 (Figure 2) engages the upper edge l|287 of the plate |28 and tilts that plate against the bias-of 'spring .|32 to swing Wheel T|22 to the positionof the dotted lines 'of "Figure 114, therbyfreeing the hub 34 from the flywheel 1| |2 and permitting tthe spool '82 (Figure 53) 'to accelerate rapidly during rewind.

When `the rack Vis held in the position -f'o'f Figure -1-2, the plate |00 'is tilted with -sumcientforce to-establish a'driving engagement between the drive wheel |06 and the shaft 32 which supports the spool '80 (Figure 3). This imparts 'rewinding lrotations fto the spool :to rewind lthe medium from spooli.

"Ihe drive mechanism for the take-up v-spo'l hub 34v may :best be understood by reference to Figure 14 which is `a'iragrnentary cross-sectional view through the axis XIV-XIV-(Fig-ure2). shown in Athis View, a friction 'wheel |20 having a tire of rubber 'or the llike is vmounted Aupon'th'e capstan shaft 16 in `alignment 'with the lfrictionv drive wheels |22'an'd |24. The latter'drive wheel bears against the wheel r|26 which is 'received upon the shaft portion ofthe hub 34. vThe'wheel |24 'has a 'tire |2421, andthewheels |22 and |26.

have no tires. lWhen the capstan shaft 16 'rotates in'the clockwise direction, as seen in Figure 14, the wheel |26 is Arotated inthe counterclockwise direction, andthe mediumg is Wound upon the "spool 82 (Figure 3) since the spool 82 is rotated inthe clockwise direction as seen in that figure. Since clockwise rotation of shaft 16, as seen 'in Figure y14, corresponds to winding the medium from the spool A|30 to the spool '82, "the spool 82 Vis rotated 'in direction corresponding "to' ther motion "imparted by 'the capstan to 'the 'medium.

The friction drive wheels 22 and |24 are supported from the shiftable support plate `|28b`y thescrews `|`22a and |2241? uwhich rideon the `inner race portions of the bearings formed on the inner portions of Ithese wheels. The plate |28 is pivotally `supported'from the `front panel 20 bythe collarv |30 which isbest seeninthe cross-sectional view'of Figure l5. 'As will beseen in the view of Figure 15, the collar '|30 rides in an opening20a of the front .panel 20 and permits tilting movement of -the vplate |528. lThe head portion |30a of Acollar |`30 'holds the .plate |28 against the panel 20.

The plate |23 is biased in -the clockwise direction `about the .collar |30, .as seenin Figure 14, by .the spring .|32 which consists of piano wire looped about -the collar .26 -and which bears at one end againsttheedge of :the panel v20 andat theother end against the recess 112821 provided inthe upper portion of the plate |20.

When vthe ,plate l|128 :is in the free position shown in Figure 14, the spring |32 rbiases .the wheels |22 land :|24 into engaging relationship with the wheels |20 and 126, jthereby causing the capstan shaft 'Hi to 'drive Athe `take--up'fspool shaft 34. However, when the member 96 swings down to the lowered position shown by the dotted lines of Figure 14, by retraction of the rack 60, the plate |28 is tilted against the bias of spring |32 and the wheels |22 and |20 are swung out of engaging relationship to discontinue the. driving action.

The plate 28 is positioned relative to the member 96 to cause disengagement of the driving action ofthe shaft 34 when the rack 60 is retracted beyond the point that the ball 66a (Figure 13) rides in the cup 60a. From the foregoing description it will be evident that knob 10 may be first rotated to retract the head 54 and disengage the drive mechanism for the capstan 14, and then a magazine may be inserted or removed from the unit without threading the medium 90 across the head, capstan, or other elements. However, after inserting a magazine, the knob 10 may be rotated until vthe ball 66a rides in the cup 6017 and holds the pinch wheel 'l2 and the head 54 against the medium 90. In this condition, the drive wheel |06 rotates the capstan 14 by reason of the engagement of friction drive wheel l with the flywheel I|2 to impart linear velocity to the medium 90. Moreover, the take-up spool 82 is yieldingly driven by the friction drive wheels |22 and |24 (Figure 14) which rotate the hub 38a to drive that spool and maintain the medium 90 taut between the capstan 14 and the spool 82. During this operation the entire carriage 52 is shifted forwardly andbackwardly by the operation of the member 48 which rides on the slot of the shaft 50 to distribute the medium 90 evenly over the axial length of the spool 82.

When the medium 90 has been completely transferred from the spool 80 (Figure 3) to the spool 82, the medium may be rewound by shifting the rack 60 downwardly beyond the point where the ball 66a rides in the cup 60a. In this condition, the plate |26 is tilted to free spool 82 from the flywheel I 2, and the plate |00 is tilted to discontinue the driving engagement of the capstan 14. Moreover, in this condition, the plate |00 shifts to cause the friction drive wheel |04 to ride in driving engagement between the wheels |06 and |03 and thereby impart take-up rotation to the spool 80 and cause the medium B0 to be wound thereon.

The gear train (Figure 2) interconnects the capstan shaft 16 with the shaft 50 which denes the groove 50a. This gear train steps down the rotation of the shaft 50 relative to the shaft I6 to cause the head or carriage 52 to ride in and out at a slow rate compared to the rotation of the spool 82.

As shown in Figure 16, a guide member 53 is attached to carriage 52 by suitable screws or similar means and extends forwardly therefrom to define a notch 53a to receive the medium 90 and guide that medium relative to the head 54, thereby avoiding any tendency of the medium to ride free of the head.

It will be noted that when the carriage 52 is shifted to the further retracted position wherein medium 90 is rewound from spool 82 to spool 80 that the shaft 50 is not rotated, and hence there is no tendency for the carriage 52 to shift axially of the shafts 34 and 32. However, the medium rewinds uniformly on the spool 80 since it is uniformly distributed across the spool 82, and there are noV elements in engagement therewith to interfere with the natural tendency of the medium Yto wind upon spool 80 in axial alignment with 10 the point on spool 82 from which it is being un- Wound.

It will be further observed that when the rewind action takes place, there are no members in contact with the record medium 90 other than the spools and 82. The head 54, the capstan T4, the pinch wheel 12, and the guide 53 are al1 in spaced positions relative to medium and have no opportunity to catch thereon or otherwire to engage the medium to tend to cause breakage thereof. Consequently, it is possible to design the drive mechanism to rotate the spool 80 during rewind at a relatively high velocity without danger of breakage, thereby to minimize the time required for rewinding the medium while at the same time avoiding breakage.

The clutch assembly, indicated generally at 25 (Figure 4) acts as a further yielding drive element between drive wheel |06 and spool 82. This clutch may, for example, consist of an annular friction plate spring biased against the face of the wheel |26, the latter being mounted to ride free of the shaft 34.

In the alternative embodiment of the present invention shown in Figures 6 and 7, the rods 42 and 44 which support the carriage 52 are not shifted inwardly and outwardly. Instead, the head 54 is mounted upon the rod |50 (Figure '7) which passes through an opening in the front panel 20 and is received on the member 49, which member includes cam following elements to ride on the groove 50a of the shaft 50 to shift the head 54 and guide medium 90 for level winding action. Head 54 is sustained from rod |50 by the arm |5I.

It will be further evident from the view 0f Figure 7 that the pinch wheel 'l2 is constructed of elongated shape similar to the capstan 14. Thus, as the head 54 is shifted inwardly and outwardly by the rod |50, the capstan 14 and pinch Wheel 72 receive the medium 90 at different points along their axes as that medium follows movement of the head 54. The capstan '|4 or the pinch wheel l2, or both, may have rubber tires since the wear is distributed over their entire axial lengths by the movement of the medium 90.

In the foregoing specification and the accompanying claims I have used the term spool to designate the devices which engage the hubs 32 and 34 and rotate with the motions of the medium 90. It is my intention to cover generically all spools, reels, pulleys and similar devices useful for this purpose.

I have used the term magnetic recorder in this specification and appended claims to designate mechanism operable either to record an intelligence upon a magnetic or similar medium, a mechanism to reproduce the intelligence contained on such a medium, or mechanism operable to accomplish both of these functions. Inasmuch as the mechanical problems encountered in all of these instruments are identical, the principles of the present invention may be applied thereto, irrespective cf the particular arrangement thereof.

While I have shown particular embodiments of my invention, it will of course be understood that I do not wish to be limited thereon since many modifications both in the elements employed and the cooperative structures disclosed may be made without departing from the spirit and scope of my invention. I, of Course, contemplate by the appended claims to cover any such modifications as fall within the true spirit and scope of my invention.

meegaan between said spools; a second wheelV mounted on saidl carriage to engage said medium and urge said medium against said.' first wheel when said carriage is positionedr close to said medium; a headmountedl on said carriage to receive said medium when said second `wheel bears thereagainst, and means to rotate one of-saidv wheels to impart velocity to said medium.

2L The combination in a magneticy recorder of a pair of spaced spool-receiving hubs to engage spools between which a lengthy record medium extends;v a capstan disposed between said hubs and spaced from said medium; a carriage; a movable`A mechanism adapted to operate upon said carriage for shifting' movements toward and away from said; medium;` a pinch wheel mounted on said carriage to bear against said` capstan tov urge said: medium against said capstan when said carriage is moved toward said medium; and a head mounted' on said carriage tov receive said medium when. said pinch wheel engages said medium.

3. lThev combination in a magneticv recorder of a pair of spaced spool-receiving hubs to engagelspool's between which a lengthy record mediunr extends; mechanism toimpart taire-up rotations to one or" said hubs to cause said inedium to be Wound on the spool engaged: thereby; a carriage having a pair` of: spaced openings; a. track' comprising two spacedi members received inv said openings to support said carriage for movements toward and awayv from said medium; and' mechanism operable to shift said track members in the axial direction relative to said oney hub uniformly to distribute said medium acrossl said spool as itis wound thereon'.

4. The combination in. a magnetic recorder of a pair`A of spaced spool-receiving hubs to engage spools between which a lengthy record medium extends; mechanism to impart; take-up rotation. to onef of said hubs to cause said medium to: be wound on the spool engaged thereby; ar carriageI having a pair of spaced openings; a track comprising twospacedf members received in said openings to support said carriage for movement toward and away from said medium; a support member for said carriage having a pair of spaced ears on opposite sides ofy said carriage and having elongated slots extending in direction transverse to the direction of movement of said carriage towards and away from said medium; a pairk of pins mounted in the opposite ends of said carriage to be received in said slots; elements including a rack and pinion adapted to shift said member toward and second position in engagement Withsaid medium to press said medium against said 'rst; wheel; an electromagnetic` transducer' head carried by saidl carriage, said head being operably positioned to. receive saidmedium when said@ secondi wheel is: movedY into engagement with saidA medium, drive elements selectively operable` to rota-te one of. said hubs and oneof said wheels to impart winding movements toA said medium; and, means interconnecting saidretractible carriagr-y` and saidj drive elements' to wind saidr medium. when said second wheel engagesysaidi first wheel.

6. The combinationin a magnetic` recorder, of a pair of spaced spool-receiving hubs to engage spools betweenv which a. lengthy record', medium extends; a rst wheel; disposed betweensaid hubs and spaced from saidmediumf; a retractable carriage including a second wheel movable to. atrst position free of said medium, a second position free of; said medium, andl a: third. position, in en gagement with saidmediumto press saidmedium against said rst wheel; an electromagnetic transducer headI carried' byl said carriag.e, said head being operably positionedy to receive. said medium when said second wheel isl moved' into engagement with said medium, driveelements operable in a rst positiony to rotate onev ofi said hubs and' one oi said". Wheels; to impart winding movements to said medium, in a'. second. condi'- tion to release said hubs, andina thirdcondition to rotatel the other of said. hubs: to impart; rewinding movements to said medium; andmechanism interconnecting said' retractable carriage and said drive elements to wind:` said medium whenV said retractable carriage is in said third position, to release said mediumA when said'v retractable carriage isin said'l second position, and torewind said medium when said' retractable car:- riage isin said rst'position.V

'7. The combination in a magnetic recorderI of a pair of` spaced spool-receiving hubs to; engage spools between which a lengthy` record' medium extends; a rst wheel disposed between said hubs and spaced from said medium ;v a retractiblecarri'age including a second; wheel' movable to aI rst position free of said medium, a second position free of said medium, and a third position in engagement with said medium topresssaid medium against said first wheel; an electromagnetic transducer head carried, byI saidI carriage, said head being operably positioned to receive said medium when said second wheel is move-d' into engagement with said medium, drive elements operable in a rst' condition to rotate one of saifd hubs and` one of said' wheels to impart winding movements to said medium, ina second condition to release said hubs, and in a third condition to rotate the other of said hubs toA impart rewinding movements to said' medium; andf means operable to urge said drive elements from said third condition to said second condition.,

8'. The combination in a magnetic recorderof a pair of spaced spool-receiving hubs to engage spools between which a lengthyy record: medium extends; a first wheel mounted in spaced relation with saidl medium; a head; a carriage. shiftable relative to said hubs to support said head.; elements including: a secondi wheelA supported'. on said carriage for retracting movementsv toward andv away from said medium selectively to press said medium against said rst wheel; means: to rotate one of said wheelsto impart velocityv to said medium and. wind said medium on. onev of said spools.

9:. The. combination in a magnetic recorder of a pair of spaced spool-receiving hubs to engage spools between which a magnetic recording medium extends; mechanism to impart take-up rotation to one of said hubs to cause said medium to be wound on the spool engaged thereby; an electromagnetic transducer head; a carriage to support said head in spaced relationship to said medium as it extends between said spools; mechanism operable in accord with rotation of said one hub to shift said carriage in the axial direction relative to the spool engaged by said hub uniformly to distribute said medium across said spool as it is wound thereon; and means including elements carried by said carriage and engageable With said medium over the entire range of shift of said head operable to press said medium against said head.

10. The combination in a magnetic recorder of a pair of spaced spool-receiving hubs to engage spools between which a lengthy record medium extends; a iirst wheel mounted in spaced relation with said medium; a head; a carriage shiftable relative to said hubs to sup-port said head; elements including a second wheel supported on said carriage for retracting movement toward and away from said medium selectively to press said medium against said first wheel; means to rotate one of said wheels to impart velocity to said Inedium and wind said medium on one of said spools; and mechanism operable to distribute said medium axially of said one spool.

11. The combination in a magnetic recorder of a pair of spaced spool-receiving hubs to engage spools between which a lengthy record medium extends; a nrst wheel mounted in spaced relation with said medium; a head; a carriage shiftable relative to said hubs to support said head; elements including a second Wheel supported on said carriage for retracting movement toward and away from said first wheel; means to rotate one of said wheels to impart velocity to said medium and wind said medium on one of said spools; and mechanism operable to distribute said medium axially of said one spool, said last mentioned mechanism including means operable to shift elements carried by said carriage in an axial direction relative to said hubs.

12. In a magnetic recorder device a pair of spaced apart rotatable spool-receiving mechanisms adapted torotatably support a pair of spools with a lengthy magnetic record medium extending therebetween through a substantially free land unobstructed path across the magnetic recorder device, a shiftable carriage mechanism, a transducer head carried by said shiftable carriage mechanism, said shiftable carriage mechanism being selectively shiftable to move said transducer head into and out of operative association with said lengthy magnetic record medium, and drive mechanism operable selectively to wind said medium on one of said spools.

13. A magnetic recorder device comprising a magnetic record medium carrying mechanism,

a shiftable carriage carrying element disposed to engage a lengthy magnetic record medium carried by said mechanism in one position of said carriage and to be disengaged therefrom in another position of said carriage, and a` transducer head disposed on the recorder device to be operatively associated with said lengthy magnetic record medium in said one position of said carriage and to be dissociated therefrom in another position of said carriage, the several parts of the magnetic recorder device :being so disposed on said device Ias to provide a substantially free path for the record medium when said carriage is in said other position, the path of said lengthy magnetic record medium being distorted when said carriage is in said one position.

14. A magnetic recorder device comprising a magnetic record medium carrying mechanism including a pair of spaced apart rotatable spoolreceiving mechanisms, a shiftable carriage carrying elements disposed to engage a lengthy magnetic record medium carried by said mechanism in one position of said carriage and to be disengaged therefrom in another position of said carriage, said shiftable carriage being disposed between said spool-receiving mechanisms and a transducer head disposed on the recorder device to be operatively associated with said lengthy magnetic record medium in said one position of said carriage and to be dissociated therefrom in another position of said carriage and disposed substantially between said spool-receiving mechanisms, the several parts of said magnetic recorder device being so disposed on said device as to provide a substantially straight line free path for the record medium when said carriage is in said other position, the path of said lengthy magnetic record medium .being distorted from a stra-ight line when said carriage is in said one position.

MARVIN CAMRAS.

References Cited in the file of this patent UNITED STATES PATENTS Number Name Date 1,123,147 Sherman Dec. 29, 1914 1,883,560 Chipman Oct. 18, 1932 1,993,735 Foster et al Mar. 12, 1935 2,051,788 Foster et al. Aug. 18, 1936 2,122,485 Nelson July 5, 1938 2,364,556 Somers Dec. 5, 1944 2,408,320 Kuhlik Sept. 24, 1946' 2,467,507 Stone Apr. 19, 1949 2,500,903 Neff Mar. 14, 1950 2,501,573 McLouth et al. Mar. 21, 1950 2,620,404 Pond Dec. 2, 1952 FOREIGN PATENTS Number Country Date 4,933 Australia Nov. 26, 1926 459,035 Great Britain Dec. 31, 1936 

